WALLACE STATE OFFICE BUILDING / 502 EAS T 9th STREET / DES MOINES, IOWA 50319 515-281-5918 TDD 515-242-5967 FAX 515-281-6794 www.iowadnr.com 

## Converting Existing Underground Storage Tank (UST) Systems to Ethanol Compatible

As higher percentages of ethanol (greater t han 10% ethanol by volume) or E-blend are blended with gasoline, owners and operators must ensure their UST syst ems are compatible. What may have been compatible with E10 is probably not compatible with a higher percent ethanol blend. Before you store or dispense E-blend, such as E 85, you must verify that your ethanol fuel path is compatible.
Ethanol guidance was developed through DNR meetings with the Fire Marshal Division, the ethanol industry, petroleum mark eters, installers and the insu rance industry. The concerns regarding E-blend are based on revi ews of available literature and research documents, which are listed at the end of this guidance documen t. The conclusion regarding E-blend fuel is straightforward: without converting to com patible equipment, your UST system could degrade and a product release could occur. Ultimat ely, the equipment and components must be compatible with the product stored.



### Concerns with E-blend Fuel Compatibility. Iowa law [567-135.4(3)] and NF PA 30, 2000 Edition (2.2.2) require UST systems to be compatible wit h the product stored. Components and equipment used for storing/dispensing conventional fuels are time tested for compatibility and readily available through your petroleum supplier. E-blend, however, does not have the same compatibility characteristics of conventional fuels when it comes to storage and dispensing. Soft metals such as zinc, brass or aluminum, which are co mmonly found in conventional fuel storage and dispensing systems, are not compatible with E85. Steel tanks and piping must be UL Marked or certified by the manufacturer for use with E-blend Fuels.
Some nonmetallic materials may also degrade w hen in contact with ethanol such as natural rubber, polyurethane, adhesives (used in older fiberglass piping), certain elastomers and polymers used in flex piping, bushings, gaskets, meters, filters, and materials made of cork. In order to store and dispense E-blend fuel, fi berglass and steel UST systems/components must be listed by UL Marked or certified by the manufacturer for use with E-blend fuels.
If you have concerns about specific storage and dispensing equipment, see New England Interstate Water Pollution Control Commission (NEIWPCC), Health and Environmental Impacts of Adding Ethanol to Gasoline in the Northeast States , July 2001, pp. 70-71. A list of E85 compatible equipment can be found at http://www.e85fuel.com/info rmation/manufacturers.htm

. Phase Separation . Ethanol is completely miscible (mixable)in water. Ethanol also blends well with gasoline. When water infiltrates a tank, (e .g., through sump covers and loose fittings at the top of the tank), the ethanol in the ethanol-gasoline ble nd will absorb the water, which, if enough2 is present, will overwhelm the ethanol’s capacity toremain blended with the gasoline. Because it mixes easier with water, the ethanol will be drawn from the gasoline into the water at the bottom, separating from the gaso line. The product in the tank is no longer a blend of ethanol and gasoline, but two layers of product--a la yer of gasoline on top and an ethanol layer on the bottom. You’re not getting an ethanol blend anymore , but a greater concentration of ethanol or gasoline. Phase separation can be a problem for v ehicles’ fuel lines as the product is no longer an ethanol blend.
Accelerated Corrosion and Conductivity . Ethanol can accelerate corrosion in steel UST systems by scouring or loosening deposits on the in ternal surfaces of tanks and piping. If a corrosion cell exists, the ethanol can accelerate (scour) the corrosion cell and cause a perforation. As mentioned above, ethanol is not compatible with soft metals such as zinc, brass, copper, lead, and aluminum. These metals will degrade or corrode in contact with ethanol and possibly contaminate a vehicle’s fuel system.
Tank leak detection equipment composed of certain metals (mentioned above), polymers and elastomers may not be compatible with ethano l. Because ethanol has a higher conductivity than gasoline, capacitance probes will not work in ethanol-blend fuels. Ve rify the floats used in magnetostrictive probes are alcohol compatible and that the ATG system is properly calibrated for ethanol. 

### Starting the Process of Converting to E-blend The conversion to E-blend fuel requires time and effort to evaluate ex isting equipment, verify compatibility and order ethanol compatible equipment. Costs are also an important consideration. There is a new three-year $13 m illion renewable fuel infrastructure program that provides grants to E-blend or biodiesel retaili ng sites. Grants can be applied for through the Iowa Department of Economic Development by clicking here

. Here are some of the procedures you will have to follow in converting your system to E-blend. The specific details are includ ed in a separate checklist, which the owner and Iowa licensed installer or professional engineer will have to complete and submit to the department.
1. Start the conversion process by obtaining the checklist of items that must be completed and signed before your system can store and dispense a E-blend

. 2. You will need to verify that components in t he fuel path are compatib le with the E-blend to be stored and dispensed. Contact your petrol eum equipment supplier or an Iowa licensed installer to discuss converting to a higher percent ethanol blend and purchasing the appropriate equipment. A list of licensed installe rs is available on our website (see p. 4).
The following equipment/components/materials mu st be compatible with the ethanol blend you intend to store and dispense (see the checklist for more details):

• Auto shutoff or overfill valve

• Tank (Is the warranty in effe ct? Is it approved by manufactu rer or UL listed for E-blend?)

• Submersible Pump, O-rings and gaskets

• Line leak detectors

• Leak Detection Equipment (ATG probes, floats, sump sensors)

• Piping material (UL listed or approved by manufacturer)3 • Thread sealant

• Flex connectors, grommets

• Filters

• Dispensers and hanging hardware (allow tw o-year phase in for compatibility)

• Spill containment and sumps

3. Your UST insurance carrier must be informed of your plans to convert to a higher percentage ethanol. They may have other requirements ot her than what the departm ent requires. The checklist requires an amended certificate of insurance.
4. No level of water is acceptable for ethanol blend fuel due to the phase separation problems. You will need to make certain all fittings and connections at the top of th e tank are tight (no vapors escape and no water enters) and that a ll sump and spill containment covers prevent water from entering. Any water intrusion problems must be fixed

5. Contact the National Ethanol Vehicle Coalition (NEVC) at 877.485.8595. The NEVC provide grants for the labors and materials for conv erting to ethanol from conventional fuels.
6. Determine costs and make your decision regardi ng the conversion. If you decide to convert, make all necessary arrangements for the c onversion with your petroleum supplier or licensed installer.

7. The tank dedicated to E-blend must be cl ean. After any water problems have been fixed, you must clean the tank dedicated to E-blend to remove all sludge from the bottom of the tank. Any sludge or particulates in the botto m of the tank will be su spended in the ethanol and cause problems with filters and fuel lines. Obtain a Clean Tank Certificate or similar documentation from the tank cl eaner after the tank is cleaned.
8. Fill pipe and access covers must be properly i dentified (API RP 1637 color code). We don’t want the transport driver to mist akenly deliver E85 to an E10 tank.)

9. The owner and an Iowa licensed installer or professional engineer must sign the ethanol compatibility checklist and submit it to the DNR. A copy of the revised certificate of insurance and the Clean Tank Certificate must accompany the checklist. 

### First Delivery and Ongoing Maintenance 1. Follow normal delivery procedur es for the first delivery of E-blend. The Renewable Fuels Association (RFA) recommends filling the tankto 80 percent capacity and to keep the tank as full as possible for 7 to 10 days 1
2. As soon as product stabilizes, a precision test (0.1 gph leak rate) is conducted with your ATG system to make sure your system is tight and the leak de tection equipment is operating properly. Report any Fail results.

1 Renewable Fuels Association (RFA), Fuel Ethanol, I ndustry Guidelines, Specifications and Procedures, December 2003, p. 154 3. You must test for water (use alcohol compatible paste if you stick your tanks) at the beginning of each shift for t he first 48 hours after delivery. 2 Checking for water regularly is a part of the ongoing maint enance with ethanol storage.
Safe Handling The safety equipment and precautions used fo r handling gasoline apply to ethanol and ethanol blend (API 1626).
Spills and Releases Ethanol blend spills and releases should be handled as they would be with gasoline. Notify the proper authorities includi ng DNR Emergency Response at515.281.8694 or 515.281.8941.

Sources: 1. New England Interstate Water Pollution Control Commission (NEIWPCC), Health, Environmental and Economic Impacts of Adding Ethanol to Gasoline in the Northeast States, Volumes 1 and 3, July 2001. 2. Renewable Fuels Association, Fuel Ethanol: Industry Guidelines, Specifications and Procedures, RFA Publication #960501, Revised December 2003. 3. US Department of Energy, National Renewable E nergy Laboratory: Handbook for Handling, Storing, and Dispensing E85, April 2002 4. US Army Information Paper, Subject: Fuel Ethanol (E85). 5. State of Delaware, Department of Natural Resources and Environmental Control, Tank Management Branch, Memorandum, Subject: Storing, Dispensing and Using Ethanol Fuel (E85), September 8, 2004. 6. Memorandum: Water Phase Separation in Oxygenated Gasoline (corrected version) by David Korotney, EPA, Chemical Engineer, Fuels Studies and Standards Branch 7. American Petroleum Institute, Storing and Handling Ethanol and Gasoline-Ethanol Blends at Distribution Terminals and Service Stations, API Recommended Practice 1626, First Edition, April 1985, Reaffirmed June 2000. 8. National Fire Protection Association (NFPA) 30, Flammable and Combustible Liquids Code, 2000 Edition; NFPA 30A Code for Motor Fuel Dispensing Facilities and Repair Garages, 2000 Edition 9. Compatibility and Permeability of Oxygenated Fuels to Materials in Underground Storage and Dispensing Equipment, Paul A. Westbrook, Ph.D., Shell Oil Company, January 1999 10. Federal Transit Administration, Clean Air Program: Summary Assessment of the Safety, Health, Environment and System Risks of Alternative Fuel, Final Report, 1995.

Websites To download DNR’s checklist for converting your UST system to E-blend or to view a list of licensed installers see http://www.iowadnr.com/land/ust/index.html For the Iowa Renewable Fuels Association (IRFA) see http://www.Iowarfa.org/ For a listing of equipment approved to handle, store and dispense E85 see http://www.pei.org/altfuels/guide.asp For the Department of Energy, EnergyEfficiency and Renewable Energy see http://www.eere.energy.gov/afd c/infrastructure/fuel_inf.html To view the Iowa Fire Marshall ethanol website: http://www.dps.state.ia.us/fm/flammable/E-85.shtml

2 Ibid.5 v. Ethanol Conversion 11.21.06